Offset printing press



sept. z2, 1925. 1,554,597

S. G. ROWLES OFFSET PRINTING PRESS Filed July. 1;, 19g;

J70/wif G. Eo )4/4 35i yingano 'Patented Sept. 22, 1925.

, UNITED STATES l v1,554,591 PATENT OFFICE.

SIDNEY eEoaeE nowLEs, or onrINoroN, ENGLAND, A ssIeNoE. or ONE-BLADE rro y rEncY norEn'r EENDER, or LoNDoN, ENGLAND.

OFFSET rniNTINe rnEss.

Application led July 11, 1923. Serial Noi 850,918. i

RowLEs, a subject of the King of Greatl Britain and,Ireland, and a resident of Or- 5 pington, countyy of Kent, England, have invented la certain new and useful 'Improvement in Offset Printing Presses, of which the following is a specification.

This invention relates to rotary printin presses constructed to print simultaneous y on both sides of 'a web, sheet, or the like in one or more colours.

In machines to effect the fore oing, two contacting resliently surfaced rol ers are 'so between, each being the complementary impressiony ylinder-of the other,and each be- -set cylinder. Such oH-set cylinders each receive superimposed multi-colour imprints from j separately inked printing rollshaving metal, stone, or similar surfaces. j Other4 proposals for multi-colour printing from one olf-set cylinder embody the use ofa plurality of stereotypes, lithographie stones or the like separately inked and im-l printing on the off-set cylinder, sometimes with the intervention o'f a second off-set cylinder in a double off-set press. The common practice of olf-set printing i. e. by conveying planographic imprints to the off-set cylinders, presents no great difficult as regards making ready or packing up ut in ada ting relief, stereo, letterpress and like worll for off-set, the exceptional diiiculties experienced generally reclude a practical success. The rotary o -set ress,

according to the present invention, a opts as one essential, the use of rubber or other resilient or flexible stereos preferably contacting directly with the off-set cylinder; these, owing to their flexibility, can easily be made -ready on the stereo rollers, and the yielding contact between stereos and off-set cylinder renders the multi-colour overprinting on the off-set cylinder for stereo work practical and successful. Further, the off- Set cylinders are comparatively unaffected by stereo pressure, and consequently good stereo-work and similar results are obtainable when two off-set cylinders co-act for simultaneous back and front printing as previously described.

Thesaid invention therefore consists of an olf-set cylinder co-acting with a second off-set cylinder, and more than one stereo yoff-set disposed as to receive a web of paper thereroller carrying resilient stereos forming impressions on each off-set cylinder, each stereo roller being independently inked, the two olf-set cylinders each being the complementary impressioncylinder of the other. Further, as will be seen from the following description and claims, novel adjustment means for various of the rollers is provided.

In order that the said invention may be `readily understood, reference is directed to the following description and accompanying drawing whichV shows in side elevation a printing machine capable of carrying out the invention.' v

Referring to the drawin" there is illustrated a construction of pnt which lends itself very conveniently to embodiment with a bag-making machine to be driven in conjunction therewith, the whole operating as a single unit formaking paper orvlike bags from a continuous web, and printing on one or both sides of the made-up bag, in anyl requisite number` of colours. The base` framework 1 may be either separate, as shown (such, for instance, when the machine is constructed as an independent plant for general off-set printing), or, such framework l may be a continuation ofthe frame of a bag-making or other machine working in unison as aforesaid. In the bed 2, the whole upper structure'S, which carries the various rollers, inking devices, adjustments, and so forth, is slidably mounted so as to beca ab1e-of transverse travel across Athe Abed to ring it into alignment with the web, sheets, or articles, being fed between the printing rollers. This transverse adjustment may be effected in any suitable manner, and the numeral 4 indicates the actuatin hand-wheel relating thereto. Mounte across the upperA structure 3 are thetwo off-set cylinders 5 and 6 which each alsl becomes the complementary impression cylinder of the other when printing on both sides is taking place. Alternatively,'the top of the sheet only can be printed, in which case 5 is merely an impression cylinder and 6 the off-set, or the bottom only can be printed, when 5 Abecomes the off-set and 6 the impression cylinder.

In the construction shown, cylinder` 5 is made the xed driving cylinder; the end s indles take a bearing throughV the side s ots 7 of the frame 3,- and whenonce positioned and adjusted, it remains permadot-and-dash line, or by other means. The

roller 6 is mounted adjustably above said fixed roller 5, and takes a bearing in a block 9 'slidably arranged in the slot 10. The block 9 is normally spring-pressed upwardly bythe side springs 11, but-is held down, keeping the roller 6 underdesired contact pressure, in the manner as hereinafter de scribed. `vAn upper. block 12, also slidable in the slot 10, carries an adjustment shaft 13, which is sup orted by resting on the saddle 14 cut in tlie head of a pin 15. The latter, by its lower extremity, rests in a recess in the up er face of the block 9. The block 12 can e forced Jdown by the screw 16, which lowers the shaft 13 and pin 15, and consequently forces down theO roller 6 against spring action. After the mainadjustment through the vscrew 16, a fine or runningadjustment to separate the rollers 5 and`6 can be effected in the following way.

vao

For a short ortion of its length the shaft 13 :is formedp with a slight cam eriphery at the oint where it is seated on t e saddle 14. T us, by partially rotating the .shaft the eccentric or cam part can be brought ou to the saddle and, block 12 being held against upward movement by the screw 16,-

the pin 15 completes the final downward movement of roller 6, `similarly the two rollers 5 and 6 can be separated by a partial rotation of shaft 13, without recourse tothe adjustment screw 16. A handle 17y is employed to carry yout the foregoing adjustment. It is to be understood that the blocks 9 and 12, the in 15, spring 11, the

eccentric part of the s aft 13, and screw 16,

areduplicated on the far side of the ina-A chine, with or without a second-handle 17. Associated with the offset rollers 5 and 6 are pairs of stereo rollers 18, 18, and 19, 19

respectively, the spindles of which are dropped into slots in the frame 3 as shown. Each spindle runs in eccentric flanged bearings which are adjustable in such a manner that rotation of the anges or plates 20 on `their own 'centres (determined by the travel Lof the arcuate slots 21 ,over the studs 22) gives la slight movement of the spindles in t their slots. By this means the stereo rollers 18,18, 19, 19, may be adjusted in relation to the olf-set rollers 5 and 6. In order to` move the top roller 6 away from the coactingroller 5, there is provided a device whereby the stereo rollers 19, 19 may simule The'means `employed consists of a rocking plate 23fxed on the shaft 13 and moving with the handle 17.. This plate 23 carriesa pair of pi-voted links 24 which each extends to its respective plate 20 where it is fixedscrew components or otherwise, thus en`4 abling the contact pressure of either stereo cylinder 19, 1-9 with the' olf-set roller 6 to be adjusted independently. By means of thel handle 17 the top assembly o f rollers 19, 19 and 6 can be movedas one complete unit with relation to the roller 5. The foui` elements, indicated as a whole by the reference numeral 2 5, represent any convenientand suitable inking gear; the rollers of which supply the stereos mounted on the stereo rollers 19, 19, and 18, 18. It will be observed that either one, two, three or four stereo rollers can be put into operation in an apparatus constructed ac cording tothe foregoing embodiment with the result that top and bottom of the sheetor the like single or together can be printed in one or two colours.v C

f In operation, assuming bth sides to be printed in two colours, the rubber or like stereo is lixed to'the rollers 19, 19 and 18,

'18, and so adjusted that one roller 19 overprints the second colour on to the olf-set roller 6 which has received one imprinting from the other roll'er 19. Similarly, the stereos on the rollers 18, 18, are adjusted to register exactly on the roller 5, and the comblned top printings from the off-set roller 6 on to the paper or the like are caused 'to' register with or print in .any

definite relation to the bottom printingsl from the lower. ofl-set roller. Although roller 5 is a printing roller, it serves as the -im ression roller for 6, andv vice `location in said frame-work, a second off-set cylinder mounted above the first olf-.set cylinder, and means for adjusting said last named off-set cylinder comprising .yieldingly izo mounted journal blocks, saddle-headed pms adapted to engage said blocks, a shaft having an eccentric portion adapted to bear against they saddle-headed pins, and a handle carried by the shaft for rotating the same whereby the pin is forced down or allowed to rise.

2. In an off-set printing machine, a framework, an off-set cylinder mounted in a fixed location in said frame-work, a second olf-set cylinder mounted above the rst olf-set cylinder, and means .for adjusting said last named off-set cylinder, a 'pair of stereo rollers mounted below the fixed off-set cylinder, and a pair of stereo rollers adjustably mounted above the upper offset cylinder, and common means for simultaneously adjusting said upper off-set cylinder and said upper stereo rollers.

3. In an olf-set printin machine, a framework, an olf-set cylin er mounted in a fixed location in said framework, a second off-set cylinder mounted above the rst olf-A set cylinder, and meansfor adjusting said last named off-set cylinder, a pair of stereo rollers mounted below the fixed oE-set cylinder, and a pair of stereo rollers adjustably mounted above the upper offset cylinder, and common means for simultaneously adjusting said upper off-set cylinder and said upper: stereo rollers, said means comprising a shaft having an eccentric portion anda pin engaging with theiadjustable mounting for the upper off-set roller, eccentric lianged bushings having the upper stereo rollers mounted therein and also having -slots lin the flanges thereof, studs on the framework of the machine and working in said slots,

`a rocking plate mounted on the shaft and having an operating handle, and links connecting said rocking plate with the flanged bushings for mounting the upper set of stereo rollers.

4. An oil-set printing machine, comprising a framewor an off-set cylinder permanently adjusted in said framework, a second olf-set cylinder adjustable relatively to the first, each being thecomplementary impression cylinder of the other, a plurality of stereo rollers to each of the olf-set cylinders, said stereo rollers being slidably mounted in the framework to be capable of adjustment relatively to their olf-set cylinders and an inkng apparatus for each stereo roller, the adjustment means for the adjustable off-set cylinder consisting in journalling its spindles Veach in a block slidably disposed in a slot in the framework, said block being normally pressed upwards by a spring, an adjustment shafty disposed over the cylinder and-parallel thereto, the shaft being rotatably carried in a second pair of ,blocks also slidable in the slots above the first-mentioned blocks, a pin with a saddle head to support the second blocks upon the first blocks and a pair of threaded studs extending through the frame to press down or release both pairs of blocks, substantially as herein described. j

In testimony whereof I `have affixedA my signature hereto this 29th day of June, 1923,

SIDNEY GEORGE EowLEs. 

